Catalysis of hydrocarbons



Patented Nov. 23, 1948 CATALYSIS' OF HYDROGARBONS John R. Bates,Swarthmore, Pa., assignor to Houdry Process Corporation, Wilmington,Dcl., .a. corporation of Delaware No Drawing. Application June 22, 1944,

. Serial No. 541,659

(Cl. 196-52l Claims.

. The present application is in .part a continuation of my copendingapplication, Ser. No. 310,762, filed December23, 193-9, and issued asPatent'No. 2,429,981, on November 4, 1947.

The present inventionrelates tonew and improved methods of catalytichydrocarbon conversion and, in particular, to improve catalystsforeffecting such conversion.

Catalytic .conversion of hydrocarbons such as the catalytic cracking ofgas oils and catalytic treating of gasoline has heretofore been knownand employed on commercial scale. The economic position of suchprocesses depends to a large extent upon the catalystemployed and,specifically, upon not only the once through activity of the catalyst,but alsoupon the production of gas and coke which are by-productsq Whilethe gas is of some utility, effectively, it maygenerally be consideredas a loss. The coke is loss. Accordingly, one of the best indications ofeconomic utility of a catalyst for hydrocarbon conversion is not theonce'through activity, but high gasoline to gas and. gasoline tocokeratios.

There is, in fact, very little fundamental knowledge or even reliabletheory to explain difierences in catalytic activity of the adsorbenttype catalyst employed in hydrocarbon conversion. For this reasonprogress along this line has been, and for some years to come willundoubtedly be, along empirical lines. The activity or lack of activityof any single component or couple of components cannot be considered asa criterion of what the activity will be when combined with otherspecific material. Accordingly, improvements in catalysis along thisline must proceed purely on the basis of trial and experiment.

Objects of the present invention are to provide new and improvedcatalysts for the conversion of hydrocarbons; to provide new andimproved hydrocarbon conversion methods in which the conversion iseffected in the presence of .a catalyst; and to provide new and.improved methods for the catalytic cracking of hydrocarbons and for thecatalytic treating of gasoline.

In accordance with a sp-ecific form of the present invention ahydrocarbon oil is contacted under conversion conditions with 'acalcined'composite of precipitated hydrous silica containing depositedzirconia and beryllia. *The conversion conditions under which thehydrocarbon oil is contacted with the composite-are such'that gaso--line boiling'range materials arecontained in. the

eflluent and coke-like material is deposited in the composite.

The calcined composite may beproduced in a getherwith either thezirconia or the beryllia and the deposition of the other upon thecoprecipi" tate. This deposition may be effected by suspending thecoprecipitate, in the moist hydrogel state, in a solution of a compoundof the third component of the composite, followed by the precipitationthereof upon the hydrogel. Deposition may likewise be effected,particularly in the case of depositing beryllia upon thesilica-zirconia, by

drying the silica-zirconia, removing alkali metal .from thesilica-zirconia, dipping the dried gel in a solution of a beryllium saltsuch as beryllium sulfate, and calcining to decompose the berylliumsulfate carried by the silica-zirconia to beryllia.

The composite may likewise be prepared by separate precipitation of thesilica, zirconia, and berylli'a and mixing of the separate precipitatesor by the coimpregnation of silica gel either in the moist undried gelstate or in the purified dried gel state with a solution containingcompounds of both zirconium and beryllium.

- Regardless of the specific method of preparation, the compositesshould be substantially freed of alkali metal materials prior tocalcination. As

is known in the art of silicious cracking catalysts,

freedom from alkali metal is desirable in order to stabilize theactivity of the catalyst. Removal of alkali metal may be effected bywashing the gel containing alkali metal either before or after drying.In some instances treatment with armmonium salts such as ammoniumchloride or sulfate or with an acid such as hydrochloric acid is ofassistance in removing the alkali metal.

/The catalyst is dried to the dried gel state and may then be calcinedfor use. The gel may be ground either before or after calcination if thecomposite is to be used in powdered form. In case it is desired to formthe composite either by molding or by extrusion into discrete pieces,the composite is ground after drying and then formed into a paste whichis either molded or extruded prior to calcination. Another form ofcatalyst is the so-called bead type catalyst in which the hydrogelstructure is not broken down, but is carried through into the finalform. When it is desired to employ this type of catalyst, the alkalimetal is removed from the hydrogel beads by dialysis and the purifiedhydrogel beads are then dried and calcined. In any case, the calcinationneed not precede hydrocarbon conversion mas-- much as the firstregeneration of the catalyst will effect the necessary calcination sothat after the initial run, all further runs will be in the presence ofcalcined composite.

The catalyst is preferably pre-calcined at a temperature between 800 and1700 F. The precalcination may be in accordance with the processdescribed in my Patent No. 2,375,757, dated May 15, 1945 in which steamis present in" amount equal to 0.3 pound per square inch partialpressure or more, or in accordance with the process described inapplication, Ser. No. 538,711, filed June 3, 1944 of H. A. Shabaker, andnow abandoned, in which water vapor is substantially with water. Asecond solution was prepared by dissolving 4.65 kilograms of zirconiumsulfate, 0.3'75 liter of 95% sulfuric acid and 0.74 kilogram ofberyllium sulfate (BeSO4.4H2O) and diluting with water to 34.5 liters.The second solution was poured into the first solution with agitation. Agel began to set in about five minutes. This gel was allowed to standfor two and one half hours to allow syneresis to occur. It was thengranulated and syneresis liquor was removed by filtration, The gel wasthen dried in an oven at 210 F.for 14 hours. The dried gel so produced,which was'glassy, was washed with water to remove free alkali metal,then treated with sucexcluded during the heat treatment which iseffected in the high temperature range between about 1500 and 1700 F.,following which, if desired, it may be calcined under the conditionsstated in my Patent No. 2,375,757. 7

The hydrocarbon oil is contacted with the catalyst under vapor phaseconversion conditions such that gasoline is contained in the efiluentand coke-like material is deposited in the catalyst. An important aspectof this invention in- Example 1 An active heat stable and regenerativecatalyst consisting essentially of substantially pure silica, zirconia,and beryllia in the approximate molar ratio of 15:1:0.9 was prepared. Toobtain this material an ammoniacal solution containing approximately1700 parts by weight of commercial sodium silicate was mixed with asolution containing about 270 parts by weight of zirconium sulfate and98 parts by weight of beryllium sulfate and of the order of 120 parts byWeight of ammonium sulfate. In about half a minute an opalescent gel,having a pH value of the order of 6.4, was formed. This gel wasfiltered, dried, washed and treated with a solution of ammonium chlorideuntil its total sodium oxide content was reduced to below 0.5% byweight. After again washing, this material was heat treated for about 2hours at controlled temperature of the order of 1100 F. The catalyst wasthen utilized for cracking a light gas oil at a catalyst temperature of800 F. at atmospheric pressure and at a space rate of 1.5. The yield of400 F, end point gasoline was approximately 40% by volume of the freshcharge.

Example 2 grams of N-brand sodium silicate to 65.5 liters cessive washesof ammonium chloride solution to remove residual alkali metal, and thenwashed with water till the wash water was free of chloride. FollpwingWashing the gel was again dried at 210 F. The purified dried gel wasground in a ball mill for 3 hours. The powdered gel was mixed with waterto form a paste which was cast in molds in which the paste was dried.The cast pellets were heat treated at 1400 F. for 10 hours in a mixtureof 5% steam and air. The catalyst so produced was employed for crackingunder the conditions stated in Example 1. A yield of 46.3% gasoline byvolume of charge was obtained. Losses to gas and coke were 3.4% and 2.7%by weight, respectively. A total liquid recovery of 99.3% by volume ofcharge was obtained. This catalyst contained 86.1% silica, 11.8%zirconia, and 2.1% beryllia.

I claim as my invention:

1. The process for the production of normally liquid low boilinghydrocarbons from heavier hydrocarbons by cracking comp-risingcontacting said heavier hydrocarbons under cracking conditions with acalcined composite of precipitated hydrous silica containing depositedzirconia and beryllia.

2. The process according to claim 1 in which the silica and zirconia arecoprecipitated.

3. The process for the production of gasoline by the cracking of heavierhydrocarbons which comprises contacting said heavier hydrocarbons undercracking conditions with a calcined composite of coprecipitated silica,zirconia, and beryllia.

4. The process for the production of gasoline boiling range hydrocarbonsfrom heavier than gasoline hydrocarbon materials which comprisescontacting said heavier than gasoline hydrocarbons under crackingconditions with a calcined composite of precipitated hydrous silica andhydrous zirconia and containing beryllia deposited therein followingdrying of the hydrous silica and hydrous zirconia and washing thereof toremove alkali metal material.

5. The process for the production of gasoline boiling range hydrocarbonsfrom hydrocarbon oil heavier than gasoline which comprises contactingsaid hydrocarbon oil under cracking conditions with a calcinedprecipitate of precipitated hydrous silica containing deposited zirconiaand beryllia which calcined composite is substantially free of alkalimetal material.

6. The process for hydrocarbon conversion comprising contacting ahydrocarbon oil under vapor phase conversion conditions such thatgasoline boiling range materials are contained in the effluent andcoke-like material is deposited, with a calcined composite ofprecipitated hydrous silica containing deposited zirconia and beryllia.

7. A catalyst for promoting hydrocarbon decomposition consisting of acalcined composite of precipitated hydrous silica containing depositedzirconia and beryllia.

8. A catalyst for promoting hydrocarbon decomposition consisting of acalcined composite of precipitated hydrous silica containing depositedzirconia and beryllia in which the silica and zirconia arecoprecipitated.

9. A catalyst for promoting hydrocarbon decomposition consistin of acalcined composite of precipitated hydrous silica containing depositedzirconia and beryllia; the silica, zirconia and beryllia in saidcatalysts being present approximately in the molar ratio of 15:1:0.9.

10. Process according to claim 6 in which the silica, zirconia andberyllia in said calcined composite are present in approximately themolar ratio of 15:1:0.9.

JOHN R. BATES.

6 REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,079,507 Johnson May 4, 19372,107,710 Perkins et a1. Feb, 8, 1938 2,129,649 Cross, Jr., et a1. Sept.13, 1938 2,129,732 Fulton et al Sept. 13, 1938 2,214,455 Egloif et a1.Sept. 10, 1940 2,280,650 Kassel Apr. 21, 1942 2,281,919 Connolly May 5,1942 2,289,757 Connolly July 14, 1942 2,289,918 Lee et a1. July 14, 19422,308,792 Thomas Jan. 19, 1943 2,331,353 Stoewener et al. Oct. 12, 19432,340,698 Ruthrufi Feb. 1, 1944

